Is Moringa oleifera a potential natural preservative for fruit juice?

G.O. Baah, I.T. Manduna, N.J. Malebo, O. de Smidt
Most fruit juice preservatives are chemically synthesised, and knowledge of the health risks associated with their consumption has resulted in the search for safer alternatives, such as secondary plant metabolites. This study evaluated the phytochemical and anti-yeast properties of acetone, methanol and water extracts from Moringa oleifera in order to explore their potential for use as preservatives in fruit juice. Qualitative phytochemical analysis indicated the presence of alkaloids, flavonoids, tannins, terpenoids, glycosides and saponins in all extracts except the water extract which lacked alkaloids. The extracts were tested against ten yeast isolates involved in fruit juice spoilage using the agar dilution assay. All plant extracts inhibited Rhodotorula dairenensis and stimulated the growth of Yarrowia lipolytica at 0.625 mg mL‑1. The methanol extract was fungicidal against Wickerhamomyces anomalus at 10 mg mL‑1, the CY0757 strain of Zygosaccharomyces bailii at 2.5 mg mL‑1 and the IGC4242 strain at 5 mg mL‑1. Growth of Saccharomyces cerevisiae (ATCC26602 and IGC3507), Lodderomyces elongisporus, Cryptococcus laurentii and Candida parapsilosis was not affected by the extracts. The acetone and water extracts exhibited the least anti-yeast activity. While M. oleifera extracts contain various secondary metabolites with anti-yeast properties, this study has demonstrated their limited potential as natural preservatives in fruit juice. However, the growth stimulatory activity of the extracts on Yarrowia lipolytica may be useful in the production of biofuels and warrants further investigation.
Baah, G.O., Manduna, I.T., Malebo, N.J. and de Smidt, O. (2021). Is Moringa oleifera a potential natural preservative for fruit juice?. Acta Hortic. 1306, 269-276
DOI: 10.17660/ActaHortic.2021.1306.34
beverage, spoilage, anti-yeast activity, secondary plant metabolites, preservation

Acta Horticulturae